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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

36362 results found.

  1. GRB 240805A: SVOM/GRM observation
  2. GRB 240805B: Enhanced Swift-XRT position
  3. GRB 240805B: LCOGT Optical Upper Limits
  4. Swift GRB 240805B: Global MASTER-Net observations report
  5. GRB 240805B: JinShan optical upper limits
  6. Fermi GRB 240805A: Global MASTER-Net observations report
  7. Swift GRB 240805A: Global MASTER-Net observations report
  8. Fermi Gamma-ray Burst Monitor trigger 744558410/240805574 is not a GRB
  9. GRB 240805A: Swift-XRT refined Analysis
  10. GRB 240805B: Swift detection of a burst
  11. GRB 240805A: Fermi-LAT detection
  12. GRB 240805A: INTEGRAL spectral analysis
  13. EP240801a: Continued optical observations at ZTSh (CraO)
  14. GRB 240805A: A long GRB detected by INTEGRAL
  15. GRB 240805A: Swift detection of a burst
  16. GRB 240805A: Fermi GBM Final Real-time Localization
  17. Fermi GRB 240804A: Global MASTER-Net observations report
  18. EP240802a: Montarrenti Observatory optical upper limit
  19. GRB 240804A: Fermi GBM Final Real-time Localization
  20. IPN triangulation of GRB 240802A / EP 240802a
  21. Fermi Gamma-ray Burst Monitor trigger 744459130/240804425 is not a GRB
  22. EP240802A: Bassano Bresciano Observatory upper limit
  23. GRB 240802A: SVOM/GRM observation
  24. EP240802a: Time coincidence with GRB 240802A and optical upper limits with Kinder observations
  25. GRB 240802A: AstroSat CZTI detection of a long burst
  26. EP240801a: further SAO RAS optical observations
  27. EP240801a: optical observations at CrAO and AbAO
  28. EP240801a: Leavitt Observatory optical observations
  29. EP240801a: SAO RAS optical observations
  30. GRB 240801B: AstroSat CZTI Updated classification - likely a solar flare
  31. GRB 240727C: SVOM/GRM observation
  32. Fermi GBM trigger 744179961 / 240801194 can not be confirmed as a GRB
  33. GRB 240730A: Swift-BAT refined analysis
  34. EP240801a: KAIT optical counterpart observations
  35. GRB 240801B: AstroSat CZTI detection of a bright long burst
  36. Fermi GRB 240801A: Global MASTER-Net observations report
  37. GRB 240801A: Fermi GBM Final Real-time Localization
  38. GRB 240730C: AstroSat CZTI detection of a long burst
  39. GRB 240731A: Fermi GBM Final Localization
  40. GRB 240731A: AstroSat CZTI detection
  41. GRB 240730A: Osservatorio Astronomico Nastro Verde upper limit
  42. GRB240730A: BOOTES-5/JGT early optical upper limit
  43. Fermi Gamma-ray Burst Monitor trigger 744061103/240730818 is not a GRB
  44. Fermi GRB 240730B: Global MASTER-Net observations report
  45. GRB 240730B: Fermi GBM Final Real-time Localization
  46. Swift GRB 240730A: Global MASTER-Net observations report
  47. GRB 240730A: Swift-XRT refined Analysis
  48. GRB 240715A: Swift-XRT afterglow detection
  49. GRB 240730A: KAIT Optical Upper Limit
  50. GRB 240727C: GRBAlpha detection
  51. GRB 240730A: Swift/UVOT Upper Limits
  52. GRB 240730A: Enhanced Swift-XRT position
  53. GRB 240730A: Swift detection of a burst
  54. GRB 240727A: Swift-BAT refined analysis
  55. Fermi Gamma-ray Burst Monitor trigger 743953682/240729575 is not a GRB
  56. GRB 240727A: observations of optical counterpart.
  57. GRB 240727B: Swift-XRT observations
  58. Fermi GRB 240727A: Global MASTER-Net observations report
  59. GRB 240727A: Swift/UVOT detection
  60. Fermi Gamma-ray Burst Monitor trigger 743868421/240728588 is not a GRB
  61. GRB 240727A: Correction to time in GCN36960
  62. GRB 240727A: Osservatorio Astronomico Nastro Verde upper limit
  63. GRB 240727A: NOT optical observation
  64. GRB 240727A: JinShan optical upper limits
  65. GRB 240727A Bassano Bresciano Observatory upper limit
  66. GRB 240727D: Correction to the GRB name in GCN 36958
  67. GRB 240727A: Fermi GBM Final Real-time Localization
  68. GRB 240727C: AstroSat CZTI detection of a long burst
  69. GRB 240727A: Swift-XRT refined Analysis
  70. GRB 240720B: GRBAlpha detection
  71. GRB 240718A: GRBAlpha detection
  72. GRB 240710B: GRBAlpha detection
  73. GRB 240627A: GRBAlpha detection
  74. Fermi GRB 240726A: Global MASTER-Net observations report
  75. GRB 240727A: Enhanced Swift-XRT position
  76. GRB 240727B: Fermi GBM Observation
  77. GRB 240727B: Swift ToO observations
  78. GRB 240727B: Swift/BAT-GUANO arcminute localization of a long burst
  79. GRB 240726A: SVOM/GRM observation
  80. GRB 240727B: AstroSat CZTI detection
  81. GRB 240726B: AstroSat CZTI detection of a short burst
  82. GRB240727A: Skynet Optical Afterglow Observations
  83. GRB 240727A: TRT optical afterglow detection
  84. GRB 240727A: KAIT Optical Afterglow Candidate
  85. GRB 240727A: Swift detection of a burst
  86. GRB 240726A: AstroSat CZTI detection of a short burst
  87. IceCube-240725A: Upper limits from a search for additional neutrino events in IceCube
  88. GRB 240726A: Fermi GBM Final Real-time Localization
  89. Swift Trigger 1244778 is not a GRB
  90. GRB 240720A: Swift-BAT refined analysis
  91. IceCube-240721A: Upper limits from a search for additional neutrino events in IceCube
  92. LIGO/Virgo/KAGRA S240716b: Upper limits from Swift/BAT-GUANO
  93. LIGO/Virgo/KAGRA S240703ad: Upper limits from Swift/BAT-GUANO
  94. Fermi Gamma-ray Burst Monitor trigger 743271526/240721680 is not a GRB
  95. Fermi Gamma-ray Burst Monitor trigger 743243582/240721356 (GRB 240721A) is not a GRB
  96. GRB 240720B: SVOM/GRM observation
  97. GRB 240721A: Fermi GBM Final Real-time Localization
  98. GRB 240720B: AstroSat CZTI detection of a short burst
  99. Fermi GRB 240720A: Global MASTER-Net observations report
  100. GRB 240720A: AstroSat CZTI detection

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